I love them all, but like Venice, I really prefer the mid size ships (70,000 ton). They are big enough to have lots of things going on, but not so big that you have to walk 15 minutes to get from one show to the other! Also, you avoid the mega crowds since you'll have about 1500 less passengers aboard.
David -- the Inspiration has been my favorite too! For several reasons - service, size, food, memories of my father, activities, cruise director - are to just name a few! Venice...........you took the words out of my mouth! I am at that age.............that is why I like the midship cruises the most! Not that I don't like the mega ones, but I can do without all the crowds and walking 15 min each time I go to my cabin! But, I will go on any ship - if the price is right!
We just got back from a cruise this past week on Carnival's smallest ship. We did have a great time but we have decided we are going back to the largest ships in the future. The larger ships have bigger varieties in food, entertainment, onboard shopping, etc......plus if you have kids they definately need a broader variety of activities that the larger ships offer. Our kids did get bored a couple times last week on the smaller ship and that has never happened before when we cruised on the big ones. We also had a lot of vibration from the engine on the small ship, and not just in our cabin. You could feel the vibration all over the ship on all the decks.
Well I've only sailed Carnival and I haven't been on a Mega ship yet (that's in October) but I can say I have been on the Holiday and the Sensation and they both have their upsides. I think my favorite was the Sensation because it was just the right size. Not too big, not too small.